Drilling device



G. W. SCHROCK DRILLING DEVICE Filed Oct. g, 192:5

- INVENTOR 1 a SC/UQO/Q.

WITNESSES A TTORNE YS Patented Dec. 16, 1924.

v UNITED STATES GEORGE W. SGHROCK, OF KELLOGG, IDAHO.

DRILLING DEVICE.

Application filed October 6, 1923. Serial No. 667,003.

To all whom it may concern: I

Be itlmown that I, GEORGE W. Sonnocn, a citizen of the United States, and a resident of Kellogg, in the county of Shoshone and State of Idaho, have invented certain new and useful Improvements in Drilling Devices, of which the following is a specification.

This invention relates to drilling devices especially adapted for use in oil and gas wells.

Briefly stated an important object of this invention is to provide a drilling mechanism having novel means whereby a limited yieldable connection is rovided between the drill bit and the diilling cable so that the strain on the drilling cable is reduced to a minimum when lifting the drill bit.

A further object is to provide a drilling mechanism wherein the cushioning mechanism is interposed in the jars in such a manner that the spring is protected from engagement with any objects or obstructions in the well which would be likely to damage the spring.

A further object is to provide a drilling mechanism of the character specified which is of highly simplified construction, durable in'use and cheap to manufacture.

Other objects and advantages will be apparent during the course of the following description.

In the accompanying drawing forming a part of this application and in which like numerals are employed to designate like parts throughout the same,-

Figure 1 is a side elevation of the improved mechanism;

Figure 2 is a side elevation of the mechanism the view being taken at right angles to Flgure 1 and parts being shown in section; and

Figure 3 is a group perspective of the improved mechanism, the parts being disassembled.

In the drawing wherein for the purpose of illustration is shown a preferred embodiment of the invention, the numeral 5 designates a bit attaching member having means of any suitable nature whereby the bit may be attached thereto.

The upper portion of the stem 5 is provided with an attaching pin 6 slidable through the cross member 7 of a jar section 8. More specificall the lower portion of the jar section 8 is ormed with a rectangusection 8 may bulm-p so as to cause the bit to engage the rock or other formation with a crushing effect. On the upward movement of the jar section 8 of the end wall 7 engages a coil spring 14 on the pin 6 and compresses the spring. The upper end of the spring is in turn engaged by a nut 16 threaded on the terminal portion of the pin.

It will be seen that a yieldable connection is provided between the jar section 8 and the stem 5 so that the drilling cable will not be unduly strained and so that the same will not kink or stretch.

It might be stated that a plurality of attaching sections or joints 20 are joined, as indicated at 21 and 22, and form a means whereb the jar section 8 may be connected to the chilling cable. The lower portions of the several joints 20 are pro-vided with an-' nular enlargements 24 by means of which the gripping members of a fishing tool may be securely engaged with the joints 20 in case a fish ing job is necessary.

Attention is especially directed to the fact that a U-shaped holding member 30 is provided with a bight portion 32 having a central opening 33 which receives the terminal of the pin 6 and the side members of the U-shaped holding member 30 are arranged on opposite sides of the end wall 7 and are connected to the enlargement 20, as indicated at 14'. The particular function of the U-shaped member 30 is to hold the nut 16 in place and to protect the spring 14 from engagement with objects which would be like] to injure the same.

With reference to the foregoing description, taken in connection with the accompanying drawing, it will be seen that the tool may be lifted from engagement with the formation being drilled without undue strain on the drilling cable. As the drilling operation progresses the diameter of the cutter is somewhat decreased and consequently the hole formed thereby greatly decreases in diameter. Therefore, when a newly dressed bit is introduced into the well, the same is likely to stick in the bottom of the hole. For this reason the yieldable connection between the drilling cable and the bit prevents i the drilling cable from being iinduly strained and possible breaking.

Having thus described the invention What is claimed is:

1. A drilling mechanism comprising a ar section having a longitudinal opening and a lower end wall, a dI'lll attaching stem having a pin slidable through the lower end wall of said jar section, a spring confined between the lower end wall of said jar section and the-upper end of said pin, and a U-shaped holding member having a bight portion connected to said pin and having side branches arranged exteriorly of said opening and connected to said stem.

2. A drilling mechanism comprising a jar section having a longitudinal opening and an end wall, a stem having a pin slidable through said end wall and having a retaining member, a coil spring confined between said retaining member and said lower end wall of the jar secti0n,'a U-shaped holding member having a bight portion connected to said pin and holding said retaining member in position, the sides of said U-shaped holding member being slidably engaged? with said lower end wall, the upper portion of said stem being provided with an enlargement arranged in the path of travel of the lower end wall of said jar section, and means connecting the lower terminal portions of said U-shaped holding member with said enlargement, said spring being arranged between and protected by the sides of said U-shaped holdin member. a v

G ORGE W. SCHROCK. 

